Visited today but did not see any charger outside.
I couldn't find any picture beforehand, but while I was on location I checked &Charge and someone added pictures there. We see the chargers in an underground parking in front of 2 "Besucher" parking spots.
I assume it's the parking lot for the Huttlerpark estate opposite Agrola. There's a ramp going underground relatively close to where the marker is, I assume that's the entrance. I didn't try to enter. The ramp curves and I couldn't see if there's a gate at the bottom.